A number of approaches, including surgery, chemotherapy and radiation, to cancer therapy have been used. Surgery is a traditional approach in which all or part of a tumor is removed from the body. Surgery generally is only effective for treating the earlier stages of cancer. For more than 50% of cancer patients by the time they are diagnosed, they are no longer candidates for effective surgical treatment. Surgical procedures may increase tumor metastases through blood circulation during surgery. Most of cancer patients do not die from the cancer at the time of diagnosis or surgery, but rather die from the metastasis and the recurrence of the cancer.
Other therapies are also often ineffective. Radiation therapy is only effective for local cancer therapy at early and middle stages of cancer, and is not effective for the late stages of cancer with metastasis. Chemotherapy can be effective, but there are severe side effects, e.g., vomiting, low white blood cells (WBC), loss of hair, loss of weight and other toxic effects. Because of the extremely toxic side effects, many cancer patients cannot successfully finish a complete chemotherapy regimen. Some cancer patients die from the chemotherapy due to poor tolerance to the chemotherapy. The extreme side effects of anticancer drugs are caused by the poor target specificity of such drugs. The drugs circulate through most normal organs of patients as well as intended target tumors. The poor target specificity that causes side effects also decreases the efficacy of chemotherapy because only a fraction of the drugs is correctly targeted. The efficacy of chemotherapy is further decreased by poor retention of the anti-cancer drugs within the target tumors.
Immunotherapy, including the use of cancer vaccines, such as autologous vaccines, is effective for cancer patients with tumor burdens of less than 108 tumor cells. Immunotherapy is often used as an adjunctive therapy in combination with other therapies such as surgery, radiation therapy and chemotherapy to clear out the remaining tumor cells. Immunotherapy and the use of tumor vaccines have not proven effective against a tumor burden greater than 5×109 to 1011 tumor cells, which is typical in a patient with small, symptomatic metastases. In addition, autologous tumor vaccination involves complicated procedures and requires a tumor specimen be processed for each patient to be treated.
Alcohol intratumoral injection therapy has been applied in clinical practices in the treatment of liver neoplasms and others cancers. Alcohol injection therapy alone does not kill all tumor cells because of the limiting volume of alcohol that can be injected, coagulating necrosis of normal living tissues caused by alcohol, alcohol dilution by the blood in the tumor to non-effective concentrations, especially when treating the large tumors and other factors. Alcohol cannot be injected close to critical structures, such as the central nervous system. Alcohol intratumoral injection therapy also has been administered with certain anti-tumor agents that are co-injected (Yu et al. (1994) J. Current Oncology, 1:97-100). In these protocols, the coagulated mass of tissue resulting from the alcohol injection serves as a slow release depot for the anti-tumor agent.
At present, there is no effective treatment for patients with high tumor burdens. Since early stage tumors are not easily detectable, many patients who are diagnosed with cancer are at the later stages of cancer with the tumor burden greater than 5×109 to 1011 tumor cells, or the tumor has already metastasized into other tissues. For these patients, traditional cancer therapies such as surgery, radiation therapy and chemotherapy may no longer be effective and/or suitable.
Despite some progress of cancer therapy, there are few, if any, effective treatments. Due to the severity and breadth of neoplasm, tumor and cancer, there is a great need for effective treatments of such diseases or disorders. An ideal cancer therapy should have the potency to eradicate systemic tumor at multiple sites in the body and the specificity to discriminate between neoplastic and non-neoplastic cells. Therefore, it is an object herein to provide treatments for such diseases and disorders. In particular, it is an object herein to provide a cancer therapy that has the potency to eradicate systemic tumor at multiple sites in the body and the specificity to discriminate between neoplastic and non-neoplastic cells.